PORT ADELAIDE will be forced to make at least one change for its clash with Fremantle in Perth on Sunday afternoon.

Tom Jonas has been ruled out for at least a month with a knee injury, which he suffered in the Power’s 36-point win over St Kilda last weekend.

One of Jack Hombsch, Jasper Pittard or untried big man Jarrod Lienert could come into the side to replace Jonas in defence.

Sam Gray and Pittard missed the Round 16 clash with the Saints but will both come into consideration after training with the main group this week.

Jimmy Toumpas has been in very good form in the SANFL, while Todd Marshall found plenty of the football against Woodville West Torrens despite not hitting the scoreboard.

Karl Amon was again one of the best for the Magpies collecting 27 disposals against the Eagles, and will be in the selection mix.

Port’s team to face the Dockers will be named on Thursday evening.

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